How to Calculate Heparin Drip Rate?
Verify the number of Heparin units in the IV bag and the volume of fluid in the bag.
Divide the number of units of Heparin in the IV bag by the number of milliliters of fluid in the bag to get the number of units per milliliter. For example, for a 1-liter (1,000-milliliter) bag of D5W with 40,000 units of Heparin, 40,000 ÷ 1,000 = 40. Therefore, the IV bag has a concentration of 40 units per milliliter (U/mL) of Heparin.
Verify the number of units of Heparin per hour the physician has prescribed.
Divide the number of units per hour that the physician prescribed for the patient by the number of units of Heparin per milliliter of IV solution. For example, if the physician prescribed 880 units per hour of Heparin, and the IV bag has a concentration of 40 units per milliliter, then 880 ÷ 40 = 22. Therefore, the drip rate for the IV should be 22 milliliters per hour.